Home networking and automation have become more popular. With the number and complexity of audio/video equipment increasing, some homeowners are interested in operating their equipment more easily. Other homeowners are more concerned about the security and safety of their homes. These homeowners may want to remotely monitor their homes, remotely control appliances and other power line devices, and learn when important events occur. For example, an important event can be the hot water heater bursting or leaking, or another type of event. Power line devices are devices that connect to the power line, usually through a plug that connects to an electrical outlet.
Currently, there are two popular home networking infrastructures. The first is phone line networking. To provide in-home networking of computers and computer peripherals without requiring home rewiring, as is usually required with standard Ethernet networks, the Home Phone line Networking Alliance (HomePNA) was formed to leverage the existing phone lines in homes. More detailed information regarding the HomePNA can be found on the Internet at www.homepna.com. While phone line networking allows homeowners to create small local-area networks (LAN's) within their homes for the purposes of connecting computers and computer peripherals, it has limitations. Significantly, phone line networking typically does not allow homeowners to control appliances, lamps, and other power line devices within their homes.
A second home networking infrastructure is power line networking. Power line networking provides ubiquitous wired connectivity throughout the majority of homes. One type of power line networking is known as X10. X10 is a communications protocol that allows for remotely controlling power line devices, such as lamps and appliances. More detailed information regarding the X10 protocol can be found on the Internet at ftp://ftp.scruz.net/users/cichlid/public/x10faq.
Current power line networking, such as X10 networking, is limited. The X10 protocol, for example, provides only a rudimentary and low-level framework for controlling and monitoring power line devices. The framework generally does not allow for sophisticated and complex device control applications. While automation systems employing existing X10 technology can be implemented using computers, more typically the systems are implemented with relatively less intelligent control centers that only govern a limited number of power line devices, in a limited manner. When computers are used, the resulting systems are still far from ideal. They may be difficult to use, and may not be reliable or robust against equipment failures and crashes.
An intelligent, reliable, and robust automation system that overcomes these problems is described in the cofiled patent application entitled “Automation System for Controlling and Monitoring Devices and Sensors”. The automation system includes system management daemons to detect problems within the system and initiate appropriate recovery actions. There can be more than one instance of each daemon for redundancy purposes. To determine which instance is the leader instance that should actively respond to requests made to the daemon, a weak leader approach is used. This approach is the subject of this patent application.